Perl next Statement


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The Perl next statement starts the next iteration of the loop. You can provide a LABEL with next statement where LABEL is the label for a loop. A next statement can be used inside a nested loop where it will be applicable to the nearest loop if a LABEL is not specified.

If there is a continue block on the loop, it is always executed just before the condition is about to be evaluated. You will see the continue statement in separate chapter.

Syntax

The syntax of a next statement in Perl is −

next [ LABEL ];

A LABEL inside the square braces indicates that LABEL is optional and if a LABEL is not specified, then next statement will jump the control to the next iteration of the nearest loop.

Flow Diagram

Perl next statement

Example

#!/usr/local/bin/perl

$a = 10;
while( $a < 20 ){
   if( $a == 15)
   {
       # skip the iteration.
       $a = $a + 1;
       next;
   }
   print "value of a: $a\n";
   $a = $a + 1;
}

When the above code is executed, it produces the following result −

value of a: 10
value of a: 11
value of a: 12
value of a: 13
value of a: 14
value of a: 16
value of a: 17
value of a: 18
value of a: 19

Let's take one example where we are going to use a LABEL along with next statement −

#!/usr/local/bin/perl

$a = 0;
OUTER: while( $a < 4 ){
   $b = 0;
   print "value of a: $a\n";
   INNER:while ( $b < 4){
      if( $a == 2){
          $a = $a + 1;
          # jump to outer loop
          next OUTER;
      }
      $b = $b + 1;
      print "Value of b : $b\n";
   }
   print "\n";
   $a = $a + 1;
}

When the above code is executed, it produces the following result −

value of a: 0
Value of b : 1
Value of b : 2
Value of b : 3
Value of b : 4

value of a: 1
Value of b : 1
Value of b : 2
Value of b : 3
Value of b : 4

value of a: 2
value of a: 3
Value of b : 1
Value of b : 2
Value of b : 3
Value of b : 4

perl_loops.htm

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